<template>
  <div class="component-upload-image">
    <el-upload multiple :action="uploadImgUrl" accept=".png,.jpeg,.jpg" list-type="picture-card" :before-upload="beforeAvatarUpload" :on-success="handleUploadSuccess" :limit="limit" :on-error="handleUploadError" :on-exceed="handleExceed" ref="imageUpload" :on-remove="handleDelete" :show-file-list="true" :headers="headers" :file-list="fileList" :on-preview="handlePictureCardPreview" :class="{ hide: this.fileList.length >= this.limit }" :disabled="disabled">
      <i class="el-icon-plus"></i>
    </el-upload>

    <!-- 上传提示 -->
    <div class="el-upload__tip" slot="tip" v-if="showTip">
      请上传
      <template v-if="fileSize"> 大小不超过 <b style="color: #f56c6c">{{ fileSize }}MB</b> </template>
      <template v-if="fileType"> 格式为 <b style="color: #f56c6c">{{ fileType.join("/") }}</b> </template>
      的文件
    </div>

    <el-dialog :visible.sync="dialogVisible" title="预览" width="800" append-to-body>
      <img :src="dialogImageUrl" style="display: block; max-width: 100%; margin: 0 auto" />
    </el-dialog>
  </div>
</template>

<script>
import { getToken } from '@/utils/auth'
import { isExternal } from '@/utils/validate'

export default {
  name: 'ImageUpload',
  props: {
    value: [String, Object, Array],
    // 图片数量限制
    limit: {
      type: Number,
      default: 1
    },
    // 大小限制(MB)
    fileSize: {
      type: Number,
      default: 5
    },
    // 文件类型, 例如['png', 'jpg', 'jpeg']
    fileType: {
      type: Array,
      default: () => ['png', 'jpg', 'jpeg']
    },
    // 是否显示提示
    isShowTip: {
      type: Boolean,
      default: true
    },
    // 是否禁用
    disabled: {
      type: Boolean,
      default: false
    }
  },
  data() {
    return {
      number: 0,
      uploadList: [],
      httpurl: 'http://1.94.210.234:8080/',
      dialogImageUrl: '',
      dialogVisible: false,
      hideUpload: false,
      baseUrl: 'http://1.94.210.234:8080/api',
      uploadImgUrl: 'http://1.94.210.234:8080/api/common/upload', // 上传的图片服务器地址
      headers: {
        Authorization: 'Bearer ' + getToken()
      },
      fileList: []
    }
  },
  watch: {
    value: {
      handler(val) {
        if (val) {
          // 首先将值转为数组
          const list = Array.isArray(val) ? val : this.value.split(',')
          // 然后将数组转为对象数组
          this.fileList = list.map(item => {
            if (typeof item === 'string') {
              if (item.indexOf(this.baseUrl) === -1 && !isExternal(item)) {
                item = { name: this.baseUrl + item, url: this.baseUrl + item }
              } else {
                item = { name: item, url: item }
              }
            }
            return item
          })
        } else {
          this.fileList = []
          return []
        }
      },
      deep: true,
      immediate: true
    }
  },
  computed: {
    // 是否显示提示
    showTip() {
      return this.isShowTip && (this.fileType || this.fileSize)
    }
  },
  methods: {
    // 上传前loading加载
    handleBeforeUpload(file) {
      if (this.disabled) {
        this.$modal.msgError('组件已禁用，无法上传文件')
        return false
      }

      let isImg = false
      if (this.fileType.length) {
        let fileExtension = ''
        if (file.name.lastIndexOf('.') > -1) {
          fileExtension = file.name.slice(file.name.lastIndexOf('.') + 1)
        }
        isImg = this.fileType.some(type => {
          if (file.type.indexOf(type) > -1) return true
          if (fileExtension && fileExtension.indexOf(type) > -1) return true
          return false
        })
      } else {
        isImg = file.type.indexOf('image') > -1
      }

      if (!isImg) {
        this.$modal.msgError(`文件格式不正确，请上传${this.fileType.join('/')}图片格式文件!`)
        return false
      }
      if (file.name.includes(',')) {
        this.$modal.msgError('文件名不正确，不能包含英文逗号!')
        return false
      }
      if (this.fileSize) {
        const isLt = file.size / 1024 / 1024 < this.fileSize
        if (!isLt) {
          this.$modal.msgError(`上传头像图片大小不能超过 ${this.fileSize} MB!`)
          return false
        }
      }
      this.$modal.loading('正在上传图片，请稍候...')
      this.number++
    },
    // 文件个数超出
    handleExceed() {
      this.$modal.msgError(`上传文件数量不能超过 ${this.limit} 个!`)
    },
    // 上传成功
    handleUploadSuccess(res, file) {
      if (res.code === 200) {
        // console.log('进入了上传成功', res)
        const index = res.data.lastIndexOf('/')
        const name = res.data.substring(index + 1)
        const uploadedFile = {
          name: name,
          url: this.httpurl + res.data
        }
        this.fileList.push(uploadedFile)
        this.uploadedSuccessfully()
        // console.log(this.fileList)

        // 更新 v-model 绑定的值
        this.$emit('input', this.fileList.map(item => item.url).join(','))

        // 检查文件列表数量是否达到限制
        if (this.fileList.length >= this.limit) {
          this.hideUpload = true
        }
      } else {
        this.beforeAvatarUpload()
        this.number--
        // this.$modal.closeLoading()
        // this.$modal.msgError(res.message)
        // this.$refs.imageUpload.handleRemove(file)
        // this.uploadedSuccessfully()
      }
    }, // 删除图片
    handleDelete(file) {
      const findex = this.fileList.map(f => f.name).indexOf(file.name)
      if (findex > -1) {
        this.fileList.splice(findex, 1)
        this.$emit('input', this.listToString(this.fileList))
      }
    },
    // 上传失败
    beforeAvatarUpload(file) {
      if (file.typ != '') {
        const isJPG = file.type === 'image/jpeg' || file.type === 'image/png'
        const isLt5M = file.size / 1024 / 1024 < 2
        if (!isJPG) {
          this.$message.error('上传头像图片只能是png、jpg 格式!')
        }
        if (!isLt5M) {
          this.$message.error('上传头像图片大小不能超过 5MB!')
        }
        //
        return isJPG && isLt5M
      }
    },
    // 上传失败
    handleUploadError() {
      this.$message.error('上传图片失败，请重试')
      // this.$modal.closeLoading()
    },
    // 上传结束处理
    uploadedSuccessfully() {
      if (this.number > 0 && this.uploadList.length === this.number) {
        this.fileList = this.fileList.concat(this.uploadList)
        this.uploadList = []
        this.number = 0
        this.$emit('input', this.listToString(this.fileList))
        this.$modal.closeLoading()
      }
    },
    // 预览
    handlePictureCardPreview(file) {
      this.dialogImageUrl = file.url
      this.dialogVisible = true
    },
    // 对象转成指定字符串分隔
    listToString(list, separator) {
      let strs = ''
      separator = separator || ','
      for (let i in list) {
        if (list[i].url) {
          strs += list[i].url + separator
        }
      }
      return strs != '' ? strs.substr(0, strs.length - 1) : ''
    }
  }
}
</script>

<style scoped lang="less">
// .el-upload--picture-card 控制加号部分
::v-deep.hide .el-upload--picture-card {
  display: none;
}

// 去掉动画效果
::v-deep .el-list-enter-active,
::v-deep .el-list-leave-active {
  transition: all 0s;
}

::v-deep .el-list-enter,
.el-list-leave-active {
  opacity: 0;
  transform: translateY(0);
}

// 禁用样式
::v-deep .el-upload.is-disabled .el-upload--picture-card {
  cursor: not-allowed;
  background-color: #f5f7fa;
}
</style>